﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.Windows.Forms;
namespace Resources
{
   public  class BitmapToRegion
    {
        //This method uses only safe code (no pointers) to scan an imagine
        //and create a region from it
        public static Region getRegion(Bitmap inputBmp, Color transperancyKey, int tolerance)
        {
            //Stores all the rectangles for the region
            GraphicsPath path = new GraphicsPath();

            //Scan the image
            for (int x = 0; x < inputBmp.Width; x++)
            {
                for (int y = 0; y < inputBmp.Height; y++)
                {
                    if (!colorsMatch(inputBmp.GetPixel(x, y), transperancyKey, tolerance))
                        path.AddRectangle(new Rectangle(x, y, 1, 1));
                }
            }

            //Create the Region
            Region outputRegion = new Region(path);

            //Clean up
            path.Dispose();

            //Finish
            return outputRegion;
        }

        private static bool colorsMatch(Color color1, Color color2, int tolerance)
        {
            if (tolerance < 0) tolerance = 0;
            return Math.Abs(color1.R - color2.R) <= tolerance &&
                   Math.Abs(color1.G - color2.G) <= tolerance &&
                   Math.Abs(color1.B - color2.B) <= tolerance;
        }

         

       
        public static void CreateControlRegion(Control control, Bitmap bitmap)
        {
            // Return if control and bitmap are null

            if (control == null || bitmap == null)
                return;

            // Set our control's size to be the same as the bitmap

            control.Width = bitmap.Width;
            control.Height = bitmap.Height;

            // Check if we are dealing with Form here

            if (control is System.Windows.Forms.Form)
            {
                // Cast to a Form object

                Form form = (Form)control;

                // Set our form's size to be a little larger that the bitmap just 

                // in case the form's border style is not set to none in the first 

                // place

                form.Width += 15;
                form.Height += 35;

                // No border

                form.FormBorderStyle = FormBorderStyle.None;

                // Set bitmap as the background image

                form.BackgroundImage = bitmap;

                // Calculate the graphics path based on the bitmap supplied

                GraphicsPath graphicsPath = CalculateControlGraphicsPath(bitmap);

                // Apply new region

                form.Region = new Region(graphicsPath);
            }

            // Check if we are dealing with Button here

            else if (control is System.Windows.Forms.Button)
            {
                // Cast to a button object

                Button button = (Button)control;

                // Do not show button text

                button.Text = "";

                // Change cursor to hand when over button

                button.Cursor = Cursors.Hand;

                // Set background image of button

                button.BackgroundImage = bitmap;

                // Calculate the graphics path based on the bitmap supplied

                GraphicsPath graphicsPath = CalculateControlGraphicsPath(bitmap);

                // Apply new region

                button.Region = new Region(graphicsPath);
            }
        }

        private static GraphicsPath CalculateControlGraphicsPath(Bitmap bitmap)
        {
            // Create GraphicsPath for our bitmap calculation

            GraphicsPath graphicsPath = new GraphicsPath();

            // Use the top left pixel as our transparent color

            Color colorTransparent = bitmap.GetPixel(0, 0);

            // This is to store the column value where an opaque pixel is first found.

            // This value will determine where we start scanning for trailing 

            // opaque pixels.

            int colOpaquePixel = 0;

            // Go through all rows (Y axis)

            for (int row = 0; row < bitmap.Height; row++)
            {
                // Reset value

                colOpaquePixel = 0;

                // Go through all columns (X axis)

                for (int col = 0; col < bitmap.Width; col++)
                {
                    // If this is an opaque pixel, mark it and search 

                    // for anymore trailing behind

                    if (bitmap.GetPixel(col, row) != colorTransparent)
                    {
                        // Opaque pixel found, mark current position

                        colOpaquePixel = col;

                        // Create another variable to set the current pixel position

                        int colNext = col;

                        // Starting from current found opaque pixel, search for 

                        // anymore opaque pixels trailing behind, until a transparent

                        // pixel is found or minimum width is reached

                        for (colNext = colOpaquePixel; colNext < bitmap.Width; colNext++)
                            if (bitmap.GetPixel(colNext, row) == colorTransparent)
                                break;

                        // Form a rectangle for line of opaque pixels found and 

                        // add it to our graphics path

                        graphicsPath.AddRectangle(new Rectangle(colOpaquePixel,
                                                   row, colNext - colOpaquePixel, 1));

                        // No need to scan the line of opaque pixels just found

                        col = colNext;
                    }
                }
            }

            // Return calculated graphics path

            return graphicsPath;
        }
    }

}
